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Explain why benzene is colourless whereas azo dyes (such as methyl yellow) are coloured.

Azo dyes are coloured because they contain alternating single and double bonds, known as a conjugated system. This creates and areas of delocalisation above and below the plane of the molecule. This area ...

Answered by Amy S. • Chemistry tutor

40200 Views

a) Find the general solution to the differential equation: f(x)=y''-12y'-13y=8. b) Given that when x=0, y=0 and y'=1, find the particular solution to f(x).

First consider y''-12y'-13y=0.

Try: y=e^mx. This gives y'=me^mxand y''=m²e^mx.

Substituting into the differntial equation we get: m²e

Answered by Antonia P. • Further Mathematics tutor

5968 Views

How do I write the function 3cosθ+4sinθ in the form Rsin(θ + α), where R and α are positive constants?

Split it up into steps:

Step 1: Use compound angle trigonometric formula to re-write Rsin(θ + α)

Since generally sin(θ ± φ) = sinθcosφ ± cosθsinφ

Rsin(θ + α) = R(sinθcosα + cos...

Answered by Oliver G. • Maths tutor

10928 Views

Calculate the distance of the centre of mass from AB and ALIH of the uniform lamina.

The diagram shows the lamina shape.

To begin, divide the lamina into smaller sections and calculate the area. In this example, the lamina is best divided into sections A, B and C. Calculate the are...

Answered by Chandler S. • Maths tutor

4952 Views

What is the equation for photosynthesis and what is the product used for?

Equation: carbon dioxide + water ---(with light energy)---> glucose + oxygen Glucose is the important product of the photosynthesis reaction. Some of the glucose is used in respiration to provide energ...

Answered by Isabelle R. • Biology tutor

17082 Views